Outline deployment requirements (#42)

* deployment requirements added to README.

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

* development requirements added.

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

* ENVTEST K8S version updated.

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

* matrix doc on container orchestration systems support added

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

* add documentation on updating the Operator SDK and tie it to the requirements of Kubernetes

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

* list of required actions for updating the Operator SDK added to CLUSTER_SUPPORT.md

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

---------

Signed-off-by: Michael Valdron <mvaldron@redhat.com>

CLUSTER_SUPPORT.md

@@ -0,0 +1,31 @@
+# Supported Container Orchestration Systems
+
+The devfile registry operator supports container orchestration 
+systems based on which Operator SDK version the registry operator
+is using as well as the API overlap between OpenShift and 
+Kubernetes. 
+
+|                   | OpenShift 4.12.x |
+|:-----------------:|:----------------:|
+| Kubernetes 1.25.x |        X         |
+| Kubernetes 1.26.x |        X         |
+
+## Operator SDK
+
+Current version in use by the Registry Operator is [Operator SDK v1.28.0](https://sdk.operatorframework.io/docs/upgrading-sdk-version/v1.28.0/).
+
+To update the Operator SDK, refer to [Upgrade SDK Version](https://sdk.operatorframework.io/docs/upgrading-sdk-version/) 
+and change the following
+1. Update the following Kubernetes API dependencies under 
+`go.mod` to the version supported by the chosen Operator SDK 
+version 
+    - `k8s.io/api`
+    - `k8s.io/apimachinery`
+    - `k8s.io/client-go`
+2. Update `ENVTEST_K8S_VERSION` under `Makefile` to the 
+Kubernetes version supported by the chosen Operator SDK version
+3. Make any changes necessary to the source based on the updates 
+to Kubernetes API dependencies
+4. Update the Operator SDK CLI to the version chosen
+5. Run `make bundle` to update fields to include the changes
+for updating Operator SDK and Kubernetes APIs

Makefile

@@ -17,7 +17,7 @@ BUNDLE_METADATA_OPTS ?= $(BUNDLE_CHANNELS) $(BUNDLE_DEFAULT_CHANNEL)
 # Image URL to use all building/pushing image targets
 IMG ?= quay.io/devfile/registry-operator:next
 # ENVTEST_K8S_VERSION refers to the version of kubebuilder assets to be downloaded by envtest binary.
-ENVTEST_K8S_VERSION = 1.22
+ENVTEST_K8S_VERSION = 1.26
 
 
 # Get the currently used golang install path (in GOPATH/bin, unless GOBIN is set)

README.md

@@ -10,6 +10,27 @@ The Devfile Registry operator manages the lifecycle of the following custom reso
 
 Issue tracking repo: https://github.com/devfile/api with label area/registry
 
+## Requirements
+
+Deployment cluster must meet one of the following criteria:
+
+- OpenShift Container Platform (OCP) 4.12.x
+- Kubernetes 1.25.x-1.26.x
+
+More on the support of container orchestration systems can be 
+found [here](CLUSTER_SUPPORT.md).
+
+Deployments made by the devfile registry operator must *never* target the default namespace due to incompatibility with 
+security setups.
+
+### Development
+
+- Go 1.19.x
+- Docker / Podman
+- Operator SDK 1.28.x
+
+See [Upgrade SDK Version](https://sdk.operatorframework.io/docs/upgrading-sdk-version/) for a guide on updating the Operator SDK. Ensure the Operator SDK version and the version of Kubernetes APIs match each other when updating by checking [CLUSTER_SUPPORT.md](CLUSTER_SUPPORT.md).
+
 ## Running the controller in a cluster
 
 Install cert-manager to provision self-signed certificates for the validating webhooks which are used specifically for the `ClusterDevfileRegistriesList` and `DevfileRegistriesList` CRs.  Cert manager needs to be installed in order for the controller manager to start.